Recently calibre has been crashing whenever I press any button on it (convert, edit metadata etc.). I ran the program in debug mode and got this (I found some of the fonts by searching for them and deleted them but I couldn't find others and calibre still keeps freezing):

C:\Users\Suleman Mulla>calibre-debug -g
Starting up...
Started up in 1.03299999237
FT_Stream_Open: could not open `C:/Windows/fonts/._GlobalMonospace.CompositeFont
'
FT_Stream_Open: could not open `C:/Windows/fonts/%GlobalMonospace.CompositeFont'

FT_Stream_Open: could not open `C:/Windows/fonts/.AppleDouble/GlobalMonospace.Co
mpositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/GlobalMonospace.CompositeFont/.
.namedfork/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/GlobalMonospace.CompositeFont/r
src'
FT_Stream_Open: could not open `C:/Windows/fonts/resource.frk/GlobalMonospace.Co
mpositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/.resource/GlobalMonospace.Compo
siteFont'
FT_Stream_Open: could not open `C:/Windows/fonts/._GlobalSansSerif.CompositeFont
'
FT_Stream_Open: could not open `C:/Windows/fonts/%GlobalSansSerif.CompositeFont'

FT_Stream_Open: could not open `C:/Windows/fonts/.AppleDouble/GlobalSansSerif.Co
mpositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/GlobalSansSerif.CompositeFont/.
.namedfork/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/GlobalSansSerif.CompositeFont/r
src'
FT_Stream_Open: could not open `C:/Windows/fonts/resource.frk/GlobalSansSerif.Co
mpositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/.resource/GlobalSansSerif.Compo
siteFont'
FT_Stream_Open: could not open `C:/Windows/fonts/._GlobalSerif.CompositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/%GlobalSerif.CompositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/.AppleDouble/GlobalSerif.Compos
iteFont'
FT_Stream_Open: could not open `C:/Windows/fonts/GlobalSerif.CompositeFont/..nam
edfork/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/GlobalSerif.CompositeFont/rsrc'

FT_Stream_Open: could not open `C:/Windows/fonts/resource.frk/GlobalSerif.Compos
iteFont'
FT_Stream_Open: could not open `C:/Windows/fonts/.resource/GlobalSerif.Composite
Font'
FT_Stream_Open: could not open `C:/Windows/fonts/._GlobalUserInterface.Composite
Font'
FT_Stream_Open: could not open `C:/Windows/fonts/%GlobalUserInterface.CompositeF
ont'
FT_Stream_Open: could not open `C:/Windows/fonts/.AppleDouble/GlobalUserInterfac
e.CompositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/GlobalUserInterface.CompositeFo
nt/..namedfork/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/GlobalUserInterface.CompositeFo
nt/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/resource.frk/GlobalUserInterfac
e.CompositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/.resource/GlobalUserInterface.C
ompositeFont'
FT_Stream_Open: could not open `C:/Windows/fonts/._StaticCache.dat'
FT_Stream_Open: could not open `C:/Windows/fonts/%StaticCache.dat'
FT_Stream_Open: could not open `C:/Windows/fonts/.AppleDouble/StaticCache.dat'
FT_Stream_Open: could not open `C:/Windows/fonts/StaticCache.dat/..namedfork/rsr
c'
FT_Stream_Open: could not open `C:/Windows/fonts/StaticCache.dat/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/resource.frk/StaticCache.dat'
FT_Stream_Open: could not open `C:/Windows/fonts/.resource/StaticCache.dat'
TT_Load_Simple_Glyph: Too many instructions (171)
TT_Load_Simple_Glyph: Too many instructions (177)
TT_Load_Simple_Glyph: Too many instructions (174)
TT_Load_Simple_Glyph: Too many instructions (174)
TT_Load_Simple_Glyph: Too many instructions (191)
TT_Load_Simple_Glyph: Too many instructions (206)
TT_Load_Simple_Glyph: Too many instructions (177)
TT_Load_Simple_Glyph: Too many instructions (188)
FT_Stream_EnterFrame: invalid read; expected 148 bytes, got 65
FT_Stream_ReadAt: invalid read; expected 128 bytes, got 65
FT_Stream_Open: could not open `C:/Windows/fonts/._desktop.ini'
FT_Stream_Open: could not open `C:/Windows/fonts/%desktop.ini'
FT_Stream_Open: could not open `C:/Windows/fonts/.AppleDouble/desktop.ini'
FT_Stream_Open: could not open `C:/Windows/fonts/desktop.ini/..namedfork/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/desktop.ini/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/resource.frk/desktop.ini'
FT_Stream_Open: could not open `C:/Windows/fonts/.resource/desktop.ini'
FT_Stream_Open: could not open `C:/Windows/fonts/._fms_metadata.xml'
FT_Stream_Open: could not open `C:/Windows/fonts/%fms_metadata.xml'
FT_Stream_Open: could not open `C:/Windows/fonts/.AppleDouble/fms_metadata.xml'
FT_Stream_Open: could not open `C:/Windows/fonts/fms_metadata.xml/..namedfork/rs
rc'
FT_Stream_Open: could not open `C:/Windows/fonts/fms_metadata.xml/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/resource.frk/fms_metadata.xml'
FT_Stream_Open: could not open `C:/Windows/fonts/.resource/fms_metadata.xml'
FT_Stream_Open: could not open `C:/Windows/fonts/._modern.fon'
FT_Stream_Open: could not open `C:/Windows/fonts/%modern.fon'
FT_Stream_Open: could not open `C:/Windows/fonts/.AppleDouble/modern.fon'
FT_Stream_Open: could not open `C:/Windows/fonts/modern.fon/..namedfork/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/modern.fon/rsrc'
FT_Stream_Open: could not open `C:/Windows/fonts/resource.frk/modern.fon'
FT_Stream_Open: could not open `C:/Windows/fonts/.resource/modern.fon'